One of the most notable improvements to golf equipments occurred in the early 1980's with the invention of the metalwood type golf club. The invention of the metalwood type golf club ushered in a new era of technologically advanced golf club designs that exponentially increased the performance of a driver type golf club, both in terms of distance and accuracy.
However, just like any other new ventures into unknown technological advancements, this new undertaking into unexplored design space provides numerous opportunities to investigate ways to further improve upon the basic concept in an area nobody has ever explored. U.S. Pat. No. 6,773,360 to Willett et al. shows one example of an attempt to further improve the performance of a metalwood type golf club head by incorporating weights into the body of the golf club head. Because a hollow metalwood type golf club head may generally have the ability to reduce a significant amount of weight by hollowing out the center of the golf club head, the excess weight saved can be shifted to locations that could improve the overall performance of the golf club head. More specifically, U.S. Pat. No. 6,773,360 provides a golf club head having adjustable weights, allowing the golfer to fine tune the club for his or her swing.
U.S. Pat. No. 6,354,962 to Galloway et al. shows another example of using technical advancements to take advantage of design space opened up by the advancement of the metalwood club by incorporating “variable face geometry” to the back of a striking face. Because the central core of the metalwood type golf club is hollowed out, it allows for different geometry to be incorporated into the internal wall profile of the club head by adjusting the thicknesses of the striking plate at various locations. More specifically, U.S. Pat. No. 6,354,962 shows a golf club having a striking plate having a thickness in the range of 0.010 to 0.250 inches, while the entire head may be composed of three pieces, a face, a sole, and a crown.
In addition to the above advancements in the utilization of metalwood type golf club, golf club designers have gone even further by experimenting with the usage of different materials to construct different portions of a metalwood type golf club head to achieve different performance properties. U.S. Pat. No. 5,855,526 to Honma illustrates this by teaching a golf club that combines different materials such as aluminum, stainless steel, titanium or the like for the body of the golf club; while components such as shaft sleeve are made of non-metallic material such as fiber reinforced plastic, wood or the like. Although not specifically requiring any of the golf club components to be made out of fiber reinforced plastic, U.S. Pat. No. 5,855,526's usage of the fiber reinforced plastic will become a common material used in golf club heads due to its lightweight and high strength characteristics.
U.S. Pat. No. 6,440,008 to Murphy et al. continues the trend of incorporating the aforementioned fiber reinforced plastic material into the striking face of the golf club head by disclosing a golf club having a head with a striking plate composed of a composite material and having a thickness in the range of 0.010 to 0.250 inches. U.S. Pat. No. 7,601,078 to Mergy et al. also shows the utilization non-metallic material, but this time into the rear body of the golf club head. U.S. Pat. No. 7,601,078 discloses a golf club head having a front body preferably made of metallic material and rear bodies are constructed out of a composite material in a way that the crown wall on the front body has a protruding section that mate with a recessed section of a crown wall on the rear body. The protruding section of the crown wall on the front body lies in a region of the club head that experiences the highest deflection and stress during impact with a golf ball.
Although the incorporation of fiber reinforced plastic in a golf club provides many performance benefits in reducing weight while maintaining a relative high level of structural integrity, the nature of fiber reinforced plastic tends to provide a significant amount of vibration dampening, which could also adversely affect the overall sound signature attenuation of the golf club itself via vibration. In fact U.S. Pat. No. 6,648,774 to Lee illustrates this undesirable dampening effect and tries to address this issue by combining metallic components with the composite type material. More specifically, U.S. Pat. No. 6,648,774 discloses a metal striking insert molded within the front face wall of the club head and is securely attached at the outside perimeter of the insert to the composite body and at the front corners of the composite body through the use of a sandwiched structure to offset the undesirable vibration attenuation of the composite material.
Despite all the performance gains achievable from the utilization of a composite type material, it can be seen that there is still a struggle to control the undesirable sound created by such composite type golf club heads. Attempts at controlling the sound often require the usage of a secondary material or stiffeners, which often negate the weight advantage achieved by the implementation of such composite type material. Hence, it can be seen from above, there is a need in the field for a golf club that can be constructed utilizing composite type material to take advantage of the performance benefits associated with such a material all without increased vibration damping of the golf club head to retain the acoustic sound of a golf club.